Connect Claude or ChatGPT to your tune with MCP

What MCP is

MCP, the Model Context Protocol, is an open standard that lets an AI assistant call tools in another app. Claude, ChatGPT, Claude Code, Cursor and VS Code all support it.

Without it, you copy tables and log excerpts into a chat and the assistant guesses at axes and units. With efi2000's MCP server, the assistant reads the tables, settings and logs itself, with names and units from your ECU's INI file.

What an assistant can read

• Your projects, with the vehicle details from Vehicle properties: engine, injectors, fuel, turbo and gearing.
• A summary of the ECU definition, and the list of saved tunes and restore points.
• Any table or curve with its axes and units, from the active tune, the base map or a restore point, so it can compare them.
• Settings, found by name, by their dialog label or by their help text.
• Uploaded logs: duration, write and burn markers, the tune revision the log started on, each channel's minimum, mean and maximum, and channel data over a time range.
• Live engine data, when you turn on live sharing.

Every tool is read-only. An assistant can't edit a tune, write or burn, or talk to the ECU. When it suggests a change, you make it in efi2000 yourself.

Connecting an assistant

1. Open Project → AI assistants.
2. Enter a name for the key, such as the assistant and device, and click Create key.
3. Copy the key. efi2000 keeps only a fingerprint of it, so it's shown once.
4. Add efi2000 to your assistant with the setup shown under the key.

• Claude (claude.ai, Desktop and mobile) and ChatGPT: add a custom connector and paste the address shown. It contains the key, so treat it like a password.
• Claude Code: run the claude mcp add command shown.
• Cursor, VS Code and other MCP clients: paste the JSON configuration shown.

Each key reads all of your projects. Make one key per assistant, so you can revoke one without affecting the others. The key list shows when each key was last used, and Revoke cuts off that assistant straight away.

Sharing live data

On the AI assistants page, turn on Share live data with my assistants. While it's on and the ECU is connected, the efi2000 tab shares the live channels and the last 20 seconds of history about once a second, so an assistant can watch the engine with you.

Data more than 10 seconds old is reported as not live, so the assistant doesn't read stale numbers as current. Sharing stops when you turn it off or close efi2000.

Things to ask

• Compare my VE table with the base map and tell me which areas changed most.
• Summarise my last log. Where did AFR stray from target, and what was peak boost?
• Did the pulls after my last ECU write run richer or leaner than before it?
• Find the boost control settings and explain what each one does.
• Does my spark table look sensible for my turbo and fuel?
• Watch the live data while I idle and tell me what idle RPM and AFR are doing.

The assistant is told to give table cells by their axis values, such as VE at 3000 RPM and 80 kPa, and to suggest small changes checked with a new log.

Limits

• The assistant sees what is saved to your account. Save the project and upload logs before you ask about them. Unsaved edits aren't visible.
• Logs over 24 MB are refused.
• For now, Claude and ChatGPT connect with the key in the address. Revoke a key if you think the address has been shared.
• efi2000 doesn't check an assistant's advice. Review anything it suggests before you change your tune, and never apply a change you don't understand to a running engine.

Questions

Which AI assistants work with efi2000?

Any assistant that supports MCP over HTTP, including Claude, ChatGPT, Claude Code, Cursor and VS Code.

Can the assistant change my tune or my ECU?

No. Every tool is read-only. It can't edit a tune, write or burn, or talk to the ECU.

Can I use it with a tune I built in TunerStudio?

Yes. Load the INI and import the MSQ into an efi2000 project, and the assistant reads the tune with the names and units from the INI.

How do I stop an assistant's access?

Revoke its key on the AI assistants page, and turn off live sharing.